1. Field of the Invention
This invention is in the field of blanking and forming dies and more particularly to apparatus for blanking an I.C. chip and its leads from a film segment and forming the leads bonded to the chip which leads are made of a very thin ductile electrical conductor in a single operation with the result that the chip and its leads are ready to be mounted on a substrate or to be packaged.
2. Description of the Prior Art
The development of I.C. chips, particularly medium and large scale I.C. chips and of manufacturing processes for automating connecting conductuve flexible beam leads to such chips has created a need for improved manufacturing process for blanking a chip and its leads from their carrier and forming the leads to facilitate subsequent placing of such chips and their leads of substrates or in packages for connection into electrical circuits. It is known to use a relatively long tape like carrier, similar to standand motion picture film, to which is bonded a thin metallic layer of a suitable electrical conductor such as copper, nickel or aluminum. The metal layer can be formed into lead frames of the desired configuration by conventional photo-etching processes. Subsequently, an I.C. chip is bonded to each lead frame. The prior art also teaches blanking a chip and its leads, a portion of the lead frame, and forming the leads either prior to the blanking operation or subsequent thereto as separate and distinct operations using different equipment.
The lead frame and the leads for each chip are made of very thin ductile metal, copper 0.0014 inches thick, for example, and when a chip is to be mounted on a substrate all the leads of the chip, up to forty in one example, must be formed so that they abut conductive pads of the substrate which are approximately 0.014 inches square. In forming the leads of I.C. chips, it is necessary that the angle of spring back be from 0.degree. to 5.degree.. The problem with the prior art has been that heretofore it was impossible to cut and form the leads of such thin ductile materials, to such dimensions with the desired degree of accuracy in a single operation.